Furnace apparatus



Elana Patented Feb. 8, 1927.

UNITED STATES 1,616,675 PATENT OFFICE.

JOHN E. BELL, OF BROOKLYN, NEW YORK, ASSIGNOR TO COMBUSTION ENGINEERINGCORPORATION, A CORPORATION OF NEW YORK.

FURNACE APPARATUS.

Application filed September This invention relates to furnace apparatusand it is especially useful in connection with stationary boilersburning pulverized fuel.

5 One of the primary objects of my invention is to provide an improvedarrangement of cooling screen for preventing the formation of slag,which is simple and efiective in construction, the parts of which areeasily l installed and readily accessible, and in which provision ismade for contraction and expansion.

The foregoing, together with such other objects as may hereinafterappear or are in 1 cident to my invention, I obtain by means of aconstruction which I have illustrated in preferred form in theaccompanying drawing, wherein:

Fig. 1 is a section through a boiler and furnace embodying myimprovements; and Fig. 2 is a section taken on the line 2-2 of Fi 1.

l n the drawing I have shown my improvements in connection with a boilerof substantially the horizontal type, as the invention is particularlyuseful in combination therewith. This boiler comprises one Or more drums7 the downcomer header or headers 8; the upcomer header or headers 9;and the connecting bank of tubes 1% such tubes being suitably bafiledone be e, however, 10 IlSIIlg from the bridge wall 20.

The tubes 10 extend over the outlet 11 of the combustion chamber A, suchoutlet being located in the upper part thereof and the combustionchamber bein of such size that combustion is completed t ierein.

The pulverized fuel is admitted by one or more burners B which may be ofany prefer red construction and are located in the top wall 12 of thecombustion chamber in a position to discharge the coal verticallydownward, adjacent the front wall 13. The fuel and flame stream takes aU-shaped course through the combustion chamber under the influence ofthe draft creating means, the bend in the stream being substantiallyabove the lgottom 14 of the combustion chamber.

front 1111.13.

5 In the bottom of the combustionchamber I out ten per cent of the airneeded for combustion is supplied through the burner 16, 1922. SerialNo. 538,565.

provide a water screen C composed of oppositely inclined sets of tubes16 and 17 which are connected into the header 18 at their forward ends,such header being preferably suitably anchored. The tubes 17 areconnected into the header 19 at the rear of the bridge wall 20, and thetubes 16 are similarly connected to the header 21. A plurality of pipes22 connect the header 21 with the downcomer header 8. These pipes 22 arepreferably arranged in two groups of three each at the ends of theheader 21, althou h the number thereof ma be varied as t e demands ofthe particular installation require. The pipes 22 are anchored in thefloor 23 and the portions thereabove are bent so as to take care ofexpansion and contraction. The pipes 16 and 17 expand from the front tothe rear.

In operation the screen C absorbs radiant heat from the depositcollecting on the floor 14 so as to maintain the temperature of suchdeposit below the fusion or slagging point, the deposit remaining in theform of a fine ash which is readily removable.

In order to protect the bridge wall 20 from erosion, I provide a screenD composed of a plurality of pipes 24, such pipes having their lowerends connected into the header 19, the main portion of the tubes lyinwithin the combustion chamber and exten ing substantially verticallyupward along the bridge walli20. The upper ends of the tubes24 extendrearwardly through the brid e wall and are connected into a header 25, wichtin turn is connected with one or more of the lowermost tubes'lO' ofthe boiler, the rear of such tubes being downwardly bent, as indicated,for this purpose. The header 25 is anchored, as indicated at 26.Expansion and contraction of the tubes 24 between the headers 19 and 25is taken care of by virtue of the bends in such pipes.

The screen D o erates to cool the deposit collecting on the ridge wall20 below the slag forming temperature. This deposit builds out in theform of whiskers or hairlike horns, formed by particles building out ina direction against the flow of the fuel and flame stream, the depositbreaking olf of its own weight.

The space between the tubes 24 is such as to erinit this deposit to fallto the bottom of the combustion chamber. If the deposit on the rear wallwere permitted to slag I10 it would, in running down, wash away thebridge wall.

The arrangement and connection for tne screens is simple and efiective,the various parts are easy to install and are readily accessible fromthe exterior of the combustion chamber.

Other advantages will occur to those skilled in the art.

What I claim is:

1. In a pulverized fuel burning furnace, the combination of a boilerhaving tubes; a combustion chamber; a cooling screen in the bottom ofthe chamber marginally of the zone of combustion includin two sets oftubes, a header with which bot sets are connected at one end, and headerfor each set at the other end; connected to one of said last mentioneeaders at one end and anchored at the other end; means connecting saidpipes with the downcomer header of the boiler; a second cooling screenmarginally of the combustion zone composed of tubes connected with theother of said headers at one end; and a header with which the tubes ofthe second cooling screen are connected at the other end; said lastheader being connected with a tube of the boiler.

2.111 a pulverized fuel burning furnace, the combination of a boilerhaving tubes; a combustion chamber; a cooling screen in the bottom ofthe chamber marginally of the zone of combustion including two sets oftubes, a header with which both sets are connected at one end, at theother end; pi es connected to one of said last mentioned headers at oneend and anchored at the other end; means connecting said pipes with thedowncomer header of the boiler; a second cooling screen marginally ofthe combustion zone composed of tubes connected with the other of saideaders at one end; and a header with whic the tubes of the secondcooling screen are connected at the other end; said last header be ingconnected with a tube of the boiler and being anchored; and the headercommon to both of said sets of tubes of the first screen. beinganchored.

3. In combination, a combustion chamber for burning fuel in $11 nsionhaving an outlet in its u per part or the products of combustion, aoiler over said outlet, a cooling stream above the floor of the chamberand mar 'nal of the zone of combustion and comp of tubes spaced apart topermit refuse-particles to pass freely therebetween to the said floor,said screen tubes being arranged in two rows in substantially V-form, aheader at the apex of the V common to both rows, a header for each rowinto which the opposite ends of the tubes of the respective row areconnected, said headers bein exterior of the chamber, a downcomer leaing from the boiler to the lower of said last the boiler, and means andheader for each set two headers, a second substantially upright screenwithin the chamber marginal o the zone of combustion and composed of arow of tubes, the lower ends of which are connected with the upper ofsaid last two headers, a header exterior of the chamber with which theupper ends of said tubes of the upright screen are connected, meansconnecting said last header into the circulation of for introducing thefuel to be burned in suspension.

4. In combination, a combustion chamber for burning fuel in suspensionhaving an outlet in its u per part for the products of combustion, aoiler over said outlet, a cooling screen above the floor of the chamberand mar 'nal of the zone of combustion and compose of tubes spaced apartto permit refuse particles to pass freely therebetween to the saidfloor, said screen tubes being arranged in two rows in substantially Vform, an anchored header at the apex o the V common to both rows, aheader for each row into which the opposite ends of the respective roware connected, said headers being exterior of the chamber, a downcomerleading from the boiler to the lower of said last two headers, means foranchoring said downcomer, a second substantially upright screen withinthe chamber marginal of the zone of combustion andcomposed of a-row oftubes, the lower ends of which are connected with the upper of said lasttwo headers, an anchored header exterior of the chamber with which theupper ends of said tubes of the upright screen are connected, meansconnecting said last header into the circulation of the boiler and meansfor introducing the fuel to be burned in sus ension.

5. In combination, a com ustion chamber for burning fuel in sus nsionhaving an outlet in its u per part or the products of combustion, aoiler over said outlet, a cooling screen above the floor of the chamberand mar inal of the zone of combustion and compose of tubes spaced apartto permit refuse particles-to pass freely therebetween to the saidfloor, said screen tubes bein arranged in two rows in substantially V cman anchored header at the apex of the \i common to both rows, a headerfor each row into which the opposite ends of the respective row areconnected, said headers being exterior of the chamber, a downcomerleading from the boiler to the lower of said last two headers, a secondsubstantially upright screen within the chamber marginal of the zone ofcombustion and composed of a row of tubes, nected with the, u per ofsaid last two headers, an anchore header exterior of the chamber withwhich the upper ends of said tubes of the upright screen are connected.means connecting said last header into the circulation of the boiler,and means for inthe lower ends of which are con-J troducing the fuel tobe burned in suspension.

6. In a pulverized fuel burning furnace, the combination of a boilerhaving tubes; a combustion chamber; a cooling screen in the bottom ofthe chamber marginal of the zone of combustion composed of a row oftubes, a. header into which one end, of the tubes of the screen areconnected, means'for anchorinfi said header, a header into which the oter end of the tubes of the screen are connected, a second substantiallyupright screen within the chamber marginal of the zone of combustion andcom sed of a row of tubes, the lower ends of w ic are connected withsaid last header, an anchored header exterior of the chamber with whichthe upper ends of said tubes of the upright screen are connected, meansconnecting said last header into the circulation of the boiler and meansfor introducing fuel to be burned in suspen- 51011.

In testimony whereof, I have hereunto signed my name.

J OHN E. BELL.

troducing the fuel to be burned in suspen sion.

6. In a pulverized fuel burning furnace, the combination of a boilerhaving tubes; at

b combustion chamber; a cooling screen in the bottom of the chambermarginal of the zone of combustion composed of a row of tubes, a. headerinto which one end of the tubes of the screen are connected, means foranchormg said header, a header into which the ot er end of the tubes ofthe screen are connected, a second substantially upright screen withinthe chamber marginal of the zone of JOHN E. BELL.

CERTIFICATE OF CORRECTION.

Patent No. l, 616, 675,

granted February 8, 1927.

to JOHN E. BELL.

It is hereby certified that error appears in the above mentioned patentrequiring correction as follows:

"and" claims 1 and 2 respectively, for the word printed specification ofthe Page 2, lines 17 and 35, read "a", and line 54, claim 3,

for the word "stream" read "screen"; and that the said Letters Patentshould be read with these corrections therein that t the case in thePatent Office.

he same may conform to the record of Signed and sealed this 1st day ofMarch, A. D. 1-927.

Seal.

M. J. Moore, Acting-Commissioner of Patents.

CERTIFICATE or connection.

Patent No. 1,616,675, granted February 8, 1927.

10 JOHN 1:. am.

It is hereby certified that error appears in the printed specificationof the lbove mentioned patent requiring correction as follows: Page 2.lines [7 and 35, claims 1 and 2 respectively, for the word "and" read"a", and line 54, clalm 3, for the word "stream" read "screen"; and thatthe aaidLettera Patent should be read with these corrections thereinthat the same may conform to the record of the case in the PatentOffice.

Signed and sealed this 1st day of March, A. .D. 192?.

M. J. Moore, Seal. ActinpGonmiaaiooer of Palm.

